One Drain?

[Ketchgould]

On a 32 foot sloop i would like to install one thru-hull for the galley and a tee fitting for the head sink. I also want to be able to gravity drain the holding tank via the same thru hull. Distance from galley to thruhull would be six feet. I will have a ball valve at bottom of holding tank so it will only be open when we need to dump, another seacock at hull.

Will this work? I am trying to reduce thruhulls.

What size hose would you use?

Will drains stink from occasional holding tank drops?

Thanks
Christian

[jgbrown]

Originally Posted by Ketchgould

On a 32 foot sloop i would like to install one thru-hull for the galley and a tee fitting for the head sink. I also want to be able to gravity drain the holding tank via the same thru hull. Distance from galley to thruhull would be six feet. I will have a ball valve at bottom of holding tank so it will only be open when we need to dump, another seacock at hull.

Will this work? I am trying to reduce thruhulls.

What size hose would you use?

Will drains stink from occasional holding tank drops?

Thanks
Christian

Ew!

I'm pretty sure there are good reasons not to connect sewage and sink lines.

Keep them separate imo, keep others closed when not in use, galley sink open is how I do it.

[RabidRabbit]

Don't worry about reducing thru hulls, it would be better to have more holes than combining the head waste with anything. Its commen at first to try to reduce the number of holes, but its really not that practical or any real benifit. 5 years from now you'll have all sorts of hole for reefer,A/C, bilges. Just get quality seacocks and premium hose.

[Stumble]

In a word, no it's a terrible idea.

Just envision emptying the holding tank... But you get a clog, so the waste backs up the plumbing lines and starts coming out the sink...

[boden36]

We drain the head sink into the line that feeds flush water to the head.
Our galley sink tees into our cockpit drain.
The saltwater for our head comes from the engine inlet cock ( but you need to be sure the engine can't suck air back through this line).
For quite a while our cooling water">engine cooling water came from a hose dropped into a large cockpit drain. Instead of a seacock you just pulled the hose out.
At the moment we have just one seacock for water in, and another for toilet waste out.

Regards,
Richard.

[Steve Bean]

One way to simplify the thru hull situation is to use a composting head. No water inlet, no waste water outlet. There are discussions here on CF and on Sailfar.net. Buy or make yourself.

[mcarling]

It would be a question of when not if the black water backed up into the sink.

[sailr69]

besides, is the holding tank higher then the waterline? most boats arn't

[Hudson Force]

Another reason to keep them separate would be to maintain the shortest hose lengths possible for the sewage. Odors eventually permeate the black water hoses and they usually have a shorter span between replacements. Odors will be reduced with shorter runs and plumbed without any rises.

[Ketchgould]

Excellent points. Ill use separate drains, thanks.

[GrowleyMonster]

You can tee the two sinks together. My approach is to only have ONE sink. Got two, now, and neither one is big enough to wash anything in. The vanity will become tool and spares storage. The galley sink will get tossed and I will put in a proper deep sink, and plumb fresh and salt water to it. Do you need two sinks? If you do, it is okay to tee the drains together. But as everyone else says, don't connect the head or the holding tank to them. Gray water and gray water is okay. Black water and black water, okay. Gray and black, no no no.

Do you have a shower?